Question: How does sea otter foraging behaviour and habitat use contribute to ecological change in nearshore environments?
Objective: Document seasonal and annual sea otter foraging behavior, rates of caloric intake, and activity budgets. Assess fine and broad scale habitat use, sea otter distribution and range expansion, and associated ecological effects.
Rationale: The effect of sea otters on benthic community ecology in recently re-colonized areas vs. long occupied areas (i.e. well established for decades) is expected to be measurable and different. Sea otter foraging behaviour and habitat use will be different at longer occupation sites, with use of soft sediment and seagrass habitats likely increasing as sea otters stay in one area for longer. Sea otter effects in these habitats are understudied. As sea otters continue to recover from extirpation, and expand their range in BC, understanding what drives their distribution and range expansion, and how their diets and ecological effects change are integral to an understanding of nearshore ecosystems.
Links: The sea otter work complements the habitat mapping, and nearshore ecology research elements, including studies in kelp forests, seagrass meadows, and other soft bottom habitats (ie. mudflats, sandy ecosystems). Sea otter distribution and range expansion will be integrated with a variety of abiotic and biotic drivers (MODIS data on sea surface temperature and productivity, BC shorezone data), as well as DFO’s multi-decadal time series of sea otter population survey data. Sea otter densities will be integrated with the 100 Islands Research Program to assess the role of sea otter foraging in producing kelp subsidies and associated changes in terrestrial mammal abundance. Results from this project will be compared to the contemporary and ancient kelp forest food web data to investigate evidence of sea otter presence and use by people in ancient times.